Hi Jebas,
The system FS calibration reduces the FS error to the order of the noise. 0.01% equates to 1 mV for a 10 V input. From the noise tables, the p-p noise (which is equal to 6.6 x rms noise) is less than 1 mV for all conversion times. So, yes, the system FS calibration will reduce the error to less than 1 mV.
This is a typical value. We do not specify maximum values for rms noise. So, the maximum value for the FS error post system calibration may exceed 0.01%.
Regards,
Johnny